congruity vs harmony

congruity

noun
  • The quality of agreeing; the quality of being suitable and appropriate. 

  • An instance or point of agreement or correspondence; a resemblance. 

harmony

noun
  • Agreement or accord. 

  • A literary work which brings together or arranges systematically parallel passages of historians respecting the same events, and shows their agreement or consistency. 

  • A pleasing combination of elements, or arrangement of sounds. 

  • The relationship between two distinct musical pitches (musical pitches being frequencies of vibration which produce audible sound) played simultaneously. 

  • The academic study of chords. 

  • Two or more notes played simultaneously to produce a chord. 

How often have the words congruity and harmony occurred in a corpus of books? (source: Google Ngram Viewer )